arXiv subjects

Mihai Ganciu

Publications and source records attributed to Mihai Ganciu.

4 recordsLinked to original sources

arXiv2019

HiPIMS magnetized plasma afterglow diagnostic

Deposition of thin films that are resistant to aggressive environment conditions, using the High-power impulse magnetron sputtering (HIPIMS) technique, represents a technological challenge. To establish the optimal operating conditions it is desirable to know the lifetime of the magnetized plasma at the end of the pulsed cathode current. The table-top system we developed allows one to measure the lifetime for all operating HiPIMS types, both for short and long pulses, based on the rapid increase of the current when applying a voltage pulse with very short rise time, up to a value which depends of the initial magnetized plasma characteristics.

physics.plasm-ph↗

arXiv2019

High power fast pulsed magnetron discharges

In order to improve the quality of thin film deposition by magnetron discharges, particularly by an effective ionization of the sputtered vapor, we developed an ionized physical vapor deposition method based on pre-ionized pulsed magnetron discharges operating in microsecond range (1-50 microseconds) leading to a lower breakdown delay, short fall time of the pulsed magnetron current, lower than one microsecond, a high ion-to-neutral flux ratio at the substrate, an arc free regime and good stability with very large instantaneously power.The transition to the self-sputtering regime, the reactive operation mode and the ion transport to the substrate can be modulated by the current pulse shape and duration. High cathode current densities (1-20 A/cm2) are obtained and large pressure range operation (3-300 mTorr) is demonstrated.

physics.plasm-ph↗

arXiv2016

Multipole Electrodynamic Ion Trap Geometries for Microparticle Confinement under Standard Ambient Temperature and Pressure Conditions

Trapping of microparticles and aerosols is of great interest for physics and chemistry. We report microparticle trapping in multipole linear Paul trap geometries, operating under Standard Ambient Temperature and Pressure (SATP) conditions. An 8-electrode and a 12-electrode linear trap geometries have been designed and tested with an aim to achieve trapping for larger number of particles and to study microparticle dynamical stability in electrodynamic fields. We report emergence of planar and volume ordered structures of the microparticles, depending on the a.c. trapping frequency and particle specific charge ratio. The electric potential within the trap was mapped using the electrolytic tank method. Particle dynamics was simulated using a stochastic Langevin equation. We emphasize extended regions of stable trapping with respect to quadrupole traps, as well as good agreement between experiment and numerical simulations.

physics.plasm-ph↗

arXiv2015

Multipole Traps as Tools in Environmental Studies

Trapping of microparticles, nanoparticles and aerosols is an issue of major interest for physics and chemistry. We present a setup intended for microparticle trapping in multipole linear Paul trap geometries, operating under Standard Ambient Temperature and Pressure (SATP) conditions. A 16-electrode linear trap geometry has been designed and tested, with an aim to confine a larger number of particles with respect to quadrupole traps and thus enhance the signal to noise ratio, as well as to study microparticle dynamical stability in electrodynamic fields. Experimental tests and numerical simulations suggest that multipole traps are very suited for high precision mass spectrometry measurements in case of different microparticle species or to identify the presence of certain aerosols and polluting agents in the atmosphere. Particle traps represent versatile tools for environment monitoring or for the study of many-body Coulomb systems and dusty plasmas.

physics.plasm-ph↗